Hydrangea plant named ‘WRHPBB2’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘WRHPBB2’, characterized by its upright, outwardly spreading and mounded plant habit; strong and sturdy stems; dark green-colored leaves; large mophead-type inflorescences with sterile flowers with relatively large white-colored sepals; and good winter hardiness.

Botanical designation: Hydrangea paniculata.

Cultivar denomination: ‘WRHPBB2’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct Hydrangea plant, botanically known as Hydrangea paniculata and hereinafter referred to by the name ‘WRHPBB2’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in Leende, The Netherlands. The objective of the breeding program was to develop new Hydrangea plants with strong stems and large attractive inflorescences.

The new Hydrangea plant originated from an open-pollination during the spring of 2005 of Hydrangea paniculata ‘Barbara’, disclosed in U.S. Plant Pat. No. 13,606, as the female, or seed parent with an unknown selection of Hydrangea paniculata as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated open-pollination in a controlled environment in Leende, The Netherlands in the spring of 2008.

Asexual reproduction of the new Hydrangea plant by softwood cuttings in a controlled environment in Leende, The Netherlands since the spring of 2008 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations of asexual reproduction.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘WRHPBB2’. These characteristics in combination distinguish ‘WRHPBB2’ as a new and distinct Hydrangea plant:

-   -   1. Upright, outwardly spreading and mounded plant habit.     -   2. Strong and sturdy stems.     -   3. Dark green-colored leaves.     -   4. Large mophead-type inflorescences with sterile flowers with         relatively large white-colored sepals.     -   5. Good winter hardiness.

Plants of the new Hydrangea differ from plants of the female parent, ‘Barbara’, in the following characteristics:

-   -   1. Plants of the new Hydrangea have stronger stems than plants         of ‘Barbara’.     -   2. Plants of the new Hydrangea have stronger and healthier         leaves than plants of ‘Barbara’.

Plants of the new Hydrangea can be compared to plants of Hydrangea paniculata ‘Pinky Winky’, not patented. In side-by-side comparisons, plants of the new Hydrangea differed primarily from plants of ‘Pinky Winky’ in the following characteristics:

-   -   1. Plants of the new Hydrangea had larger inflorescences than         plants of ‘Pinky Winky’.     -   2. In the autumn, sterile flowers of plants of the new Hydrangea         retained their white coloration whereas sterile flowers of         plants of ‘Pinky Winky’ became dark pink in color.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet comprises a side perspective view of a typical flowering plant of ‘WRHPBB2’ grown in an outdoor nursery.

The photograph on the second sheet is a close-up view of a typical inflorescence of ‘WRHPBB2’.

DETAILED BOTANICAL DESCRIPTION

Plants used for the aforementioned photographs and the following description were grown during the summer in ground beds in an outdoor shadehouse in Grand Haven, Mich. and under cultural practices typical of commercial Hydrangea production. Plants of the new Hydrangea were four years old when the photographs and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea paniculata ‘WRHPBB2’. -   Parentage:     -   -   Female, or seed, parent.—Hydrangea paniculata ‘Barbara’,             disclosed in U.S. Plant Pat. No. 13,606.         -   Male, or pollen, parent.—Unknown selection of Hydrangea             paniculata, not patented. -   Propagation:     -   -   Type cutting.—By softwood cuttings.         -   Time to initiate roots, summer.—About 18 days at             temperatures about 24° C.         -   Time to produce a rooted young plant, summer.—About three             months at temperatures about 24° C.         -   Root description.—Fine and thick; white and brown in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant form and growth habit.—Perennial deciduous shrub;             upright, outwardly spreading and mounded plant habit;             inverted triangle; strong and sturdy lateral branches;             freely branching habit with about 24 lateral branches             developing per plant; vigorous growth habit.         -   Plant height.—About 105 cm.         -   Plant diameter or area of spread.—About 145 cm.         -   Lateral branches.—Length: About 82 cm. Diameter: About 5 mm.             Internode length: About 6 cm. Texture: Smooth, glabrous.             Strength: Strong, sturdy. Color: Close to 187A. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 12 cm.         -   Width.—About 6.5 cm.         -   Shape.—Elliptic.         -   Apex.—Ovate.         -   Base.—Obtuse.         -   Margin.—Serrulate.         -   Texture, upper and lower surfaces.—Coarse, pubescent.         -   Venation pattern.—Pinnate.         -   Color.—Developing and fully expanded leaves, upper surface:             Close to 138A; venation, close to 145B. Developing and fully             expanded leaves, lower surface: Close to 138B; venation,             close to 145C.         -   Petioles.—Length: About 2 cm. Diameter: About 1 mm. Texture,             upper and lower surfaces: Pubescent. Color, upper surface:             Close to 59A. Color, lower surface: Close to 145A. -   Flower description:     -   -   Flower type and habit.—Single sterile and fertile flowers             arranged on terminal mophead cymes; flowers face mostly             outwardly.         -   Fragrance.—Moderately fragrant; pleasant.         -   Natural flowering season.—Plants flower throughout the             summer in Grand Haven, Mich.; flowers not persistent.         -   Quantity of flowers.—Freely flowering habit; about 32             fertile flowers and about 19 sterile flowers develop per             inflorescence.         -   Inflorescence height.—About 8.5 cm.         -   Inflorescence diameter.—About 10.5 cm.         -   Flower diameter, fertile flowers.—About 6 mm.         -   Flower depth (height), fertile flowers.—About 3 mm.         -   Flower diameter, sterile flowers.—About 4.5 cm.         -   Flower depth (height), sterile flowers.—About 3 mm.         -   Flower buds, fertile and sterile flowers.—Length: About             5 mm. Diameter: About 4 mm. Shape: Obovate. Color: Close to             155B.         -   Petals, fertile flowers only.—Quantity per flower and             arrangement: About five in a single whorl. Length: About             3 mm. Width: About 2 mm. Shape: Ovate. Apex: Acute. Base:             Cuneate. Margin: Entire. Texture, upper and lower surfaces:             Smooth, glabrous. Color: When opening, upper and lower             surfaces: Close to 155D. Fully opened, upper and lower             surfaces: Close to 155D.         -   Sepals, fertile flowers.—Quantity per flower and             arrangement: About four to six in a single whorl. Length:             About 1 mm. Width: About 0.5 mm. Shape: Subulate. Apex:             Acute. Base: Obtuse. Margin: Entire. Texture, upper and             lower surfaces: Smooth, glabrous. Color: When opening, upper             and lower surfaces: Close to 142D. Fully opened, upper and             lower surfaces: Close to 142D.         -   Sepals, sterile flowers.—Quantity per flower and             arrangement: About four to six in a single whorl. Length:             About 2 cm. Width: About 3 cm. Shape: Ovate. Apex: Broadly             acute. Base: Obtuse. Margin: Entire. Texture, upper and             lower surfaces: Smooth, glabrous. Color: When opening, upper             and lower surfaces: Close to 155C. Fully opened, upper and             lower surfaces: Close to 155C.         -   Pedicels, fertile flowers.—Angle: About 20° to 30° from             inflorescence axis. Strength: Strong, sturdy. Length: About             6 mm. Diameter: About 1 mm. Texture: Pubescent. Color: Close             to 145C.         -   Pedicels, sterile flowers.—Angle: About 30° to 40° from             inflorescence axis. Strength: Strong, sturdy. Length: About             2 cm. Diameter: About 1 mm. Texture: Pubescent. Color: Close             to 8D.         -   Reproductive organs, fertile flowers.—Stamens: Quantity per             flower: About eight. Anther shape: Round. Anther length:             About 1 mm. Anther color: Close to 197A. Pollen amount:             Scarce. Pollen color: Close to 4D. Pistils: Pistil quantity             per flower: About two. Pistil length: About 3 mm. Stigma             shape: Round. Stigma color: Close to 150D. Style length:             About 1 mm. Style color: Close to 150D. Ovary color: Close             to 145C.         -   Reproductive organs, sterile flowers.—Stamens: None observed             on plants of the new Hydrangea. Pistils: None observed on             plants of the new Hydrangea.         -   Seeds, fertile flowers only.—Quantity per inflorescence:             Numerous. Size: Less than 0.1 mm by less than 0.1 mm;             dust-like. Color: Brown. -   Disease & pest resistance: Plants of the new Hydrangea have been     observed to have resistance to root rot pathogens common to     Hydrangea plants. Plants of the new Hydrangea have not been observed     to be resistant to pests and other pathogens common to Hydrangea     plants. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about −31° C. to about     38° C. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘WRHPBB2’ as illustrated and described. 